Peel and stick waterproofing sheets and mats have been used for various purposes in construction. For example, peel and stick sheets have been used on roofs and on foundations to protect against the seepage of water into houses and buildings. The peel and stick waterproof sheets are laid out on roofs and stick directly to the plywood, or other material, that forms the structural portion of the roof. Waterproofing sheets can also be applied directly to a foundation, such as a poured-in-place wall, or other foundation material, to protect against seepage of water into a basement or other area. In fact, there are many uses for waterproofing sheets which have a peel away layer that can be stuck directly to various surfaces that require waterproofing or for other purposes, such as structural stability, such as an underlayment for tile.